Vulnerability Note VU#407641

Overview

The EMC Legato NetWorker database services use weak authentication, allowing a remote attacker to gain root access to the server.

Description

EMC Legato NetWorker is a cross-platform backup and recovery application. It is also repackaged by Sun Microsystems as Solstice Backup and StorEdge Enterprise Backup, by FSC as Fujitsu Siemens Computers' NetWorker, by NEC as WebSAM NetWorker Powered by Legato, and by Fujitsu as NetWorker.

NetWorker database services

At least two of the processes run by a NetWorker server provide database services. The database on a NetWorker server contains system configuration information, including licenses, client configurations, backup schedules, and storage devices. The server database also contains a mechanism for controlling backups remotely.

NetWorker database service authentication and authorization

NetWorker uses a token-based authentication scheme to determine the identity of a user who attempts to access the network databases. After a database client submits its credentials to the server, the server compares the credentials to an administrator list. The server then grants a token to the client that contains information about the client, including whether the client has administrative privileges.

The problem

NetWorker does not perform adequate authentication of the tokens. An attacker can create or modify a token to grant administrative privileges to himself, regardless of whether the attacker is in the administrator list. An attacker with administrative access to the NetWorker databases can gain complete control of a vulnerable NetWorker server.

Impact

An unauthenticated, remote attacker could execute arbitrary commands on the NetWorker server as root. Once the NetWorker server has been compromised, any NetWorker client machine could in turn be compromised.

You may wish to block access to the vulnerable software from outside your network perimeter, specifically by blocking access to the ports used by NetWorker (typically TCP and UDP ports 7937-9936). This will limit your exposure to attacks. However, blocking at the network perimeter would still allow attackers within the perimeter of your network to exploit the vulnerability. The use of host-based firewalls in addition to network-based firewalls can help restrict access to specific hosts within the network. It is important to understand your network's configuration and service requirements before deciding what changes are appropriate.

Vendor Information

EMC Software

Notified: June 03, 2005 Updated: August 16, 2005

Status

Vulnerable

Vendor Statement

EMC has created - and made available to customers - a set ofguidelines and software patch to better protect against thevulnerability identified in this advisory. The full guidelines areavailable at:http://www.legato.com/support/websupport/product_alerts/081605_NW_token_authentication.htmAn integrated resolution to this vulnerabilitywill be available in the next release of EMC Legato NetWorker, whichis planned to be generally available in Q4 of 2005.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

US-CERT has no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

Fujitsu Limited

Notified: August 15, 2005 Updated: August 24, 2005

Status

Vulnerable

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

There are no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

NEC

Notified: August 15, 2005 Updated: August 24, 2005

Status

Vulnerable

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

There are no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

Sun Microsystems, Inc.

Notified: July 12, 2005 Updated: September 19, 2005

Status

Vulnerable

Vendor Statement

Sun repackages the Legato Networker product as Sun StorEdge Enterprise Backup, and is affected by the vulnerability described in CERT VU#407641. Sun has published Sun Alert 101866 which is available here: